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Efficacy and Application Areas
of «RIKOR» Series X-ray Diffractometer |
|
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Every
purchase of an instrument should bring to customer a direct or
indirect benefit.
The efficacy of using a «RIKOR» Series X-ray diffractometer is
determined by its intended purpose. «RIKOR» provides for
nondestructive direct check for stress condition in parts and
structures. Such inspection enables detection and remedy of
adverse factors during manufacture and operation of parts and
facilities. The adverse factor consists in creation of large
tensile residual stresses, which, when imposed with effective
tensile stresses, can result in defects during manufacture or a
fault, accident or catastrophe during operation of parts and
facilities. |
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Application 1.
Analysis in Parts of a Satellite
Made of Titanium Alloy
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|
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Object of check –
a satellite part made of titanium alloy VT23.
Purpose of check
– to assess stress condition in semi-spheres of satellite part
at different state of their manufacture: before the flanges are
welded in (operation 1), after the flanges are welded in (operation
2), and after thermal processing (operation 3).
Check was performed at the
premises of S.P. Korolev ENERGIA RKK OJSC, the participants
being A.V. Lyuttsau, Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math.
Sc. A.D. Zvonkov, Dr. Eng. Sc. D. B. Matveev, Dr. Eng. Sc. V.N.
Sereda, A.V. Gollandtsev. |
|
Method used for stress condition
assessment
– «sin2ψ» method and vertical exposure technique.
Radiation used
– CrKα.
Check Points
-
between holes for flanges,
along the perimeter of the holes, and at a 5 - 8 mm distance
from the hole, and on the flanges being welded in.
Stress Condition Index
– since it was required to
assess, in each operation, the stress condition of the part on
the whole, the stress condition index was selected as the mean
stress value of all checkpoints. Stability of each technological
operation was assessed by the standard deviation of reference
sample.
Results
Obtained
If before flange welding the mean
stress made–97 MPa, then after flanges were welded in, a change
in the stress polarity into tensile stresses was observed: +665
MPa, and after thermal processing almost five-fold
decrease in tensile stresses was noted: +138 MPa.
The most stable operation is thermal processing (the minimal
reference sample deviation = 87 MPa), and the most unstable –
welding in flanges (ÑÎ = 177 MPa).
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Publications on the Subject
X-ray diffractometer "RIKOR"
Determining
Residual Stresses in Parts and Structures Made of Different
Steels and Alloys, A.V.Kotelkin, A.D.Zvonkov, A.V.Lyutsau,
D.B.Matveev, D.V.Dubrovin, V.N.Sereda, Abstracts
Second International Conference on X-ray and Neutron Capillary
Optics, Zvenigorod, Russia, September 22-26, 2004.
X-ray method of
determining residual stresses in moldings and parts made of
titanium, aluminum,
nickel; and other alloys / Kotelkin A.V., Zvonkov A.D., Lyuttsau
A.V., Matveev D.B., Kumakhov M.A., Ibraimov N.S. – In Collected
Articles: Die forging: perspectives and development (collected
science reviews) – GOU VPO «UGTU-UPI», 2005.
– pp. 784-790. (In Russian) |
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Application 2.
Stress Condition Check in Main
Rotor Blades of Helicopter MI-8 Made
of Aluminum Alloy
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Object of check
- seven main rotor blades of MI-8 helicopter made of alloy
AVT-1. In this instance, vanes 0, 1,
2, 3, 4, 5, 6 had operation time of 370,
795,795, 1588, 1588, 1588 hrs, respectively.
Purpose
of check
– to determine
correlation between stressed condition
of the lower berth of blade longeron and
operation time.
Check was done in the
environment of one of Air Force divisions, with participation of
A.V. Lyuttsau,
Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr.
Eng. Sc. D.B. Matveev, Dr. Eng.
Sc. V.N. Sereda, Dr. Eng. Sc. V. Ya. Maklashevsky. |
|
Method used for stress condition
assessment –
vertical exposure method.
Radiation Used
– CrÊα
Check Points
– 21 points along the lower berth of blade
longeron, equally spaced in between.
Stress Condition Index
– since it was required to assess the
condition of the part on he
whole in each operation, the stressed condition index was
selected as the mean stress of all
checkpoints.
As the stressed
condition index
in each checkpoint, the first
invariant of the principal stresses
tensor was used: σ = (σ1+ σ2)/3. The confidence interval of the
calculated stresses values under the
exposure conditions used does not exceed 10 MPa (relative error
is Δσav = +5 MPa).
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Results Obtained
 For
all checked blades on the lower berth of longeron, strongly
expressed heterogeneity of
residual stresses lengthwise was observed, characterized by
existence of areas where the residual
stresses had undergone significant changes compared to original
(vane 0). For each blade, the mean
stress value along the length σav was determined (see the table).
The resulting from correlation
analysis Pearson coefficient equal
to 0.73 evidences good correlation
between σav and operation time.
Linear approximation of the dependence
between the blade mean stress and
operation time is shown on the figure.
It follows from the obtained
functional dependence that operation
of the helicopter main rotor blades
leads to a shift of the original level
of compressing residual stresses
towards tension. |
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Application 3.
Stress Condition Check in
Aluminum Alloy Aircraft Wheel Hubs |
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Object of Check
– two used aircraft wheel hubs made of alloy AK-6, one with
strengthened working surface, the other one without.
Purpose of check
– determining the difference
between the stresses condition of aircraft wheel hubs with
strengthened versus non-strengthened
working surface.
Check was performed in the
facilities of Moscow Institute for Steed & Alloys and Rubin AK
OJSC, with participation of A.V. Lyutsau, Dr. Eng. Sc. A.V.
Kotelkin, Dr. Phys. Math. Sc. A.D.Zvonkov,
Dr. Eng. Sc. D.B. Matveev, Dr. Eng. Sc. Mozalev. |
|
Method used to assess stress
condition– «sin2ψ»
method.
Radiation used
– CrÊα.
Check points
– are depicted on the scheme.
Stressed Condition Index
– in each checkpoint, two components of
resid al stresses were
assessed: radial (σr) and tangential (σt).
Results
Obtained
The results of determ on hub
surfaces are given in tables 1 and 2.It
follows from there that the strengthened hub had
compressive residual stresses in all checkpoints whilethe
non-strengthened – mostly tensile stresses shortening its life. |
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Table 1 Stresses on the
Surface of Non-Strengthened Wheel |
|
Checkpoint
No. |
st t, MPa |
sz
z, MPa |
|
1-1 |
-90 |
+90 |
|
1-2 |
-180 |
0 |
|
1-3 |
0 |
+130 |
|
3-1 |
+20 |
-85 |
|
3-2 |
+120 |
-65 |
|
3-3 |
-205 |
-55 |
|
5-1 |
+150 |
+30 |
|
5-2 |
+170 |
+30 |
|
5-3 |
0 |
+25 |
|
9-1 |
+130 |
- |
|
9-2 |
+65 |
- |
|
9-3 |
+50 |
- |
|
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Table 2
Stresses on the Surface of Strengthened
Wheel |
|
Checkpoint
No. |
st, MPa |
sz, MPa |
|
1-1 |
-130 |
-330 |
|
1-2 |
-110 |
-200 |
|
1-3 |
-110 |
-370 |
|
3-1 |
-130 |
-190 |
|
3-2 |
-220 |
-310 |
|
3-3 |
-150 |
-370 |
|
5-1 |
-345 |
-370 |
|
5-2 |
-260 |
-320 |
|
5-3 |
-240 |
-370 |
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9-1 |
-10 |
- |
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9-2 |
-70 |
- |
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9-3 |
-130 |
- |
|
Publication on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses
in moldings and parts made of titanium,
aluminum, nickel; and other alloys / Kotelkin A.V., Zvonkov
A.D., Lyuttsau A.V., Matveev
D.B., Kumakhov M.A., Ibraimov N.S. – In Collected Articles: Die
forging: perspectives and development
(collected science reviews) – GOU VPO «UGTU-UPI», 2005. – pp.
784-790. (In Russian) |
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Application 4.
Stress Condition Check of
Aluminum Alloy Tank of Refueler
ATZ-20
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Object of Check
– tanks of refueller ATZ-20 of 20m3 capacity made of aluminum
alloy 5086.
Purpose of Check
was to determine stress condition of empty
refueller tank, and when the tank was fiiled
- mean effective stress
Check was performed
at the primises
of the Bykovo
Aircraft Repair Workshop parking
s e, with participation of A.V. Lyuttsau, Dr . Eng. Sc. A.
Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr. Eng. Sc. V.S.
Krasovsky. |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– CrÊα.
Checkpoints
– in the most stressed tank part: around
weld seam in the bottom.
Stressed Condition Index
–since the requirements
was to assess stress condition in each status of the tank on the
whole, the stress condition index was selected as the mean
stress of all check points. |
Results Obtained
Before the tank was filled (status 1), mean
stress made –110 MPa (mean
standard sample deviation = 20 MPa),
after it was filled (status 2): -55
MPa (mean standard sample
deviation = 90 MPa). Consequently, the
mean stress σe when the
refueller tank is
filled equals to +45 MPa (see the
diagram).
Publication on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses in
moldings and parts made of titanium, aluminum, nickel;
and other alloys / Kotelkin A.V., Zvonkov A.D., Lyuttsau
A.V., Matveev D.B., Kumakhov M.A.,
Ibraimov N.S. – In Collected Articles: Die forging: perspectives
and development (collected science
reviews) – GOU VPO «UGTU-UPI», 2005. – pp. 784-790. (In Russian) |
|
Application 5.
Stress Condition Check of
Chromium-Nickel Alloy Disks of Gas
Turbine Engine |
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Object of check
– six disks made of chromium-nickel alloy.
Purpose of check
– was to determine influence of operation
time on the stressed condition of strengthened disk surface.
Check was performed at the
premises of Salyut MMPP, with participation of A.V. Lyuttsau, Dr.
Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr.
Eng. Sc. D.B. Matveev. |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– CrÊα.
Checkpoints –
on one of the sides of
strengthened flat of each disk, 8 checkpoints in four sectors,
which directions coincide with symmetry axes. In each of Â, C, D,
and E directions, on desk part strengthened
by surface plastic deformation four
measurements were performed:
checkpoint 1 – next to the hole,
2 –between the holes, 3 –
under the hole, 4 – under the hole, closer to the
collar (see the schematic)
Stressed Condition Index
–since the requirements
was to assess stress condition in each operation of the part of
the whole, the stress condition index was selected as the
mean stress of all check points.
Results Obtained
Residual stresses in disk checkpoints
are very scattered both in terms of value and in terms of
polarity: from –520 MPa to +200 MPa. This evidences large
instability of the technological operation of disk flat
strengthening.
|
The results obtained are given on the diagram.
One can see that the first disk has the highest level of
compressive stresses at the comparatively longest
operation time while other disks at minimum operation
time have the least level of compressive stresses.
Consequently, depending on the quality
of surface strengthening operation,
the operation time affects differently on the change in the
residual stresses level.
Publication on
the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses in
moldings and parts made of titanium, aluminum, nickel;and other
alloys / Kotelkin A.V., Zvonkov A.D.,
Lyuttsau A.V., Matveev D.B., Kumakhov
M.A., Ibraimov N.S. – In Collected Articles: Die forging:
perspectives and development (collected science reviews) - GOU
VPO «UGTU-UPI», 2005. – pp. 784-790. (in Russian). |
|
Application
6.
Stress Condition Check of Steel
Landing Gear in Fighter SU-30MKI |
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Object of check
– four main landing gears: 1 – landing gear without operation
time; 2,3,4 – landing gears with operation time: 642; 1166; 1175
times used, respectively.
Purpose of check
– was to determine correlation
between the stressed condition of landing gear and operation
time.
Check was performed in the
premises of Sukhogo OKB OJSC, with participation of A.V.
Lyuttsau, Dr. Eng. Sc. A.V. Kotelkin,
Dr. Phys. Math
Sc. A.D. Zvonkov, Dr. Eng. Sc.
D.B. Matveev, Dr. Eng. Sc. A.A.
Saanikov |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– FeÊα.
Checkpoints
– 6 checkpoints close to weld seams.
Stress Condition Index
– residual stresses of the
unused landing hear were takes as zero, the stress
condition index for other landing
gears was the maximum, among six checkpoints,
stress increment Δσmax (for subsequent calculation of
remaining life).
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Results Obtained
The results obtained are given in the table. Correlation
analysis between the stress condition of landing
gear and its operation time shows good correlation between Δσmax
and number of times the gear was
used (Pearson coefficient r equals to 0.73). Linear
approximation of Δσmax dependence on operation
time is shown on the figure. It follows from the
resultant functional dependence that landing gear
operation leads to a shift of the original level of
residual stresses towards tension.
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Table
Maximum Stress Increment for Each Gear and
Pearson Coefficient |
|
Gear No. |
Δσmax, MPa |
Number of
Times Gear
Was Used |
r |
|
1 |
0 |
0 |
0,87
|
|
2 |
290 |
642 |
|
3 |
360 |
1166 |
|
4 |
720 |
1175 |
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Application 7.
Stress Condition Check of
Solid-Rolled Steel Railway Wheels |
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Object of check
– solid-rolled wheel with standard cone-and-plate disk.
Purpose of Check
– was to determine stress condition on the
inner and outer sides of the wheel.
Check was performed at the
premises of All-Russia Railways Transport Research Institute (VNIIZhT),
with participation of Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math.
Sc. A. D. Zvonkov, Dr. Eng. Sc. D.B. Matveev, A.V. Lyuttsau,
S.L. Shitkin. |
|
Method used to assess stress condition
- «Sin2ψ» method.
Radiation used
– FeÊα.
Checkpoints
– 6 checkpoints on the rim;
10
checkpoints on the
flat and 4 checkpoints on the center
boss on each side of the wheel.
Stress Condition Index –
was mean stress on the side in radial direction
σRav. |
|
Results
Obtained
The results obtained are given on the
diagram. On the diagram, red color marks residual stresses on
the inner side , green color on the outer side. On the inner
side of the rim, rather large compressing
stresses only are effective; on the outer side, the residual
stresses are practically absent. On the flat, compressive
residual stresses are higher on the outer side. On the
center boss, the residual stresses of compression on the inner
side and of tension on the outer side are observed. |
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Diagram of Residual
Stresses
Level
On Different
Wheel Sides
 |
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Application 8.
Stress Condition Check of the
Locomotive Pinion Made of Steel 45ÕÍ |
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Object of check
– a fragment of the locomotive pinion
made of steel 45ÕÍ (Lyublino Foundry
Mechanics Factory).
Purpose of check
– was to assess the
possibility of nondestructive quality control of
pinions’ thermal processing based on residual
stresses.
Check was performed in the
premises of the Moscow Institute of Steel & Alloys, with
participation of Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc.
A.D. Zvonkov, Dr. Eng.
Sc. D.B. Matveev, A.V. Lyuttsau, A.V. Shevchenko. |
|
Method used to assess stress condition
- «Sin2ψ» method.
Radiation used
– FeÊα.
Check points
on the butt
end surface of pinion fragment, three checkpoints at the base of
each
of six teeth.
Stress
Condition Index – in
each checkpoint, residual stresses were determined in tangential
(X) and radial (Y) directions.
Results Obtained
The results obtained are summarized in
the table.
|
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Table
Residual stresses in checkpoints in radial and
tangential directions |
|
Tooth No. |
Checkpoint No. |
Check Results |
σY, MPa
|
σX, Mpa
|
|
1 |
1-1 |
-83 |
-115 |
|
1-2 |
-1544 |
-119 |
|
1-3 |
-574 |
+90 |
|
5 |
5-1 |
-16 |
-574 |
|
5-2 |
-303 |
-349 |
|
5-3 |
-264 |
-350 |
|
2 |
2-1 |
-40 |
-131 |
|
2-2 |
-1081 |
-222 |
|
2-3 |
-728 |
+53 |
|
6 |
6-1 |
-1085 |
-207 |
|
6-2 |
-1149 |
-154 |
|
6-3 |
-1206 |
+59 |
|
3 |
3-1 |
-368 |
+26 |
|
3-2 |
-330 |
+30 |
|
3-3 |
-109 |
-110 |
|
7 |
7-1 |
-673 |
-470 |
|
7-2 |
-266 |
-57 |
|
7-3 |
-580 |
+118 |
|
4 |
4-1 |
-692 |
+906 |
|
4-2 |
-480 |
+263 |
|
4-3 |
-490 |
-546 |
|
|
One can see from the results obtained that all radial residual
stresses σY feature the nature of compression.
At that, significant variation is observed: from -1544 MPa to
–16 MPa.
The situation with tangential residual
stresses σX is much worse:
together with effective stresses they
are responsible for crack formation at
the teeth basis. There, along with compressive stresses, there
are
zones with tensile residual stresses as well. The variation in
the data obtained is even greater than for residual stresses:
from –574 MPa to +906 MPa. The variation in value obtained (1480
MPa) is comparable to the elastic limit of steel 45ÕÍ. Such
variation evidencess imperfectness
of the existent operation of
teeth surface thermal processing.
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Application
9.
Stress Condition Check of Steel
Weld Seam in Nuclear Power Industry |
|
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Object of check
– weld joint made of structural steel.
Purpose of check
– was to assess the possibility of
nondestructive check of weld joints in nuclear power plant
environment using portable x-ray diffractometer «Rikor».
Check was performed in the
premises of a nuclear power plant, with participation of Dr.
Phys. Math. Sc. A.D. Zvonkov, Dr. Eng. Sc. A.V. Kotelkin, Dr.
Eng. Sc. M.B. Barikov. |
|
Method used to assess stress condition
- «Sin2ψ» method.
Radiation used
– FeÊα.
Check Points
– in the area of weld joint thermal impact.
Stress Condition Index
– âin each checkpoint, residual
stresses were determined in tangential (στ) and axial (σax)
directions. |
|
Results Obtained
The results
obtained for residual stresses in axial (σax) and tangential (στ)
directions in different
eld joint checkpoints are given on the figure. The work done
showed the possibility of nondestructive
eck of weld joints in nuclear power plant environment using
portable x-ay diffractometer «Rikor>> |
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Application 10.
Stress Condition Check of a
Stainless Steel Measuring
made tube fragment of steel
12Õ18Í10Ò
Fragment of Weld Joints in
Nuclear Power Industry |
|
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Object of check
– a fragment of weld
joint made of austenitic steel.
Purpose of the check
– was to assess stress condition of the weld int fragment in the
seam and thermally affected area.
Check was performed in the
premises of IRO LLC, with participation of A.V. Lyuttsau, Dr.
Eng. Sc. D.B. Matveev, Dr. Phys. Math. Sc. N.S. Ibraimov, Dr.
Eng. Sc. V.G.Lyuttsau, A.A. Bolotokov |
|
Method used to assess stress condition
- «Sin2ψ» method.
Radiation used
– CrÊα.
Check
points
in the weld joint seamand
thermally affected area.
Stress
Condition Index– in
each checkpoint, residual stresses were determined in axial
direction. |
|
Results Obtained
Residual stresses are presented on the figure below, where
checkpoint 0 is the
middle of the seam, checkpoints 1 and 6 are 9 mm, checkpoints 2
and 7 are 24 mm, checkpoint 3 and 8 are 45 mm, checkpoints 4 and
9 are 60 mm, checkpoints 5 and 10 are 24 mm, checkpoints 6 and
11
are 97 mm from the middle of the seam. At the bottom of the
figure, the residual stresses in the weld seam and closer than 9
mm from it are presented. These stresses were obtained
with the help of polycapillary collimation system of 0.5 mm in
diameter.
|
|
 |
|
Publications on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses
in moldings and parts made of titanium, aluminum, nickel; and
other alloys / Kotelkin A.V., Zvonkov A.D., Lyuttsau A.V.,
Matveev D.B., Kumakhov M.A.,
Ibraimov N.S. – In Collected articles: Die forging: perspectives
and development (collected science
reviews) – GOU VPO «UGTU-UPI», 2005. – pp. 784-790. (in
Russian). |
|
Application11.
Stress Condition Check of Steel
Gas-Line Weld Joint Fragment |
|
 |
Object of check
– a fragment of gas pipe weld joint.
Purpose of check
– was to assess stress condition of weld
joint in thermally affected area of the gas
line fragment having the operation time of τ2=17 years and that
of gas line fragment with operation time τ1 = 0 years.
Check was done in the premises
of All-Russia Gas Research Institute (VNIIGAZ), with
participation of Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc.
A.D. Zvonkov, Dr. Eng. Sc. D.B. Matveev, A. V.
Lyuttsau, Dr. Eng. Sc. V.N. Sereda |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– FeÊα.
Check Points: three
checkpoints at different distances from the
longitudinal weld seam.
Stress
condition index
– (s1
+ s2)/3.
Results Obtained
The diagramm represents residual stresses read from checkpoints
1…3 in case of 0 years operation time (red color), and 17 years
operation time (green color). The data obtained show that the
original level of tensile residual stresses in the said
checkpoints considerably grows after seventeen years of
operation, to a greater extend – in the nearest to the weld seam
checkpoint, and to a lesser extend – in the third
checkpoint.
 |
Publications on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses in
moldings and parts made of titanium, aluminum, nickel; and other
alloys / Kotelkin A.V., Zvonkov A.D., Lyuttsau A.V., Matveev
D.B., Kumakhov M.A.,
Ibraimov N.S. – In Collected Articles: Die forging:
perspectives and development (collected science reviews) –
GOU VPO «UGTU-UPI», 2005. – pp. 784-790. (in Russian).
|
|
Application 12.
Stress Condition Check of Steel
Metal Columns of the Christ the Savior
Cathedral |
|
 |
Object of check
– four steel supporting columns in the ground
floor of the Christ the Savor Cathedral (the Synod Cathedral).
Purpose of check
– was to assess stress
condition of the supporting metal columns.
Check was performed during
construction in Moscow of the largest Christ the Savior
Cathedral (Synod Cathedral), with participation of A.V. Lyuttsau,
Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr.
Eng. Sc. D.V. Matveev |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– FeÊα.
Check Points
– column base.
Stress Condition Index
– (s1
+ s2)/3. |
Results Obtained
Check
has revealed that three columns were loaded equally. The fourth
column was somewhat unloaded as regards other columns.
 |
|
|
|
Application 13.
Stress Condition Check of Steel
Elements of Bridges |
|
Upon request from Gormost FGUP, the
Krymsky and Borodinsky Bridges across the Moscow River were
checked
 |
|
 |
Object of check
– load- bearing chains
and ties of the Krymsky Bridge, structural elements of the
Borodinsky bridge
Purpose of check
– was to assess stress
condition of the structural elements of bridges.
Check was performed
in Moscow
condition with
participation
A.V. Lyutsau, Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math.
Sc. A.D. Zvonkov, Dr. Eng. Sc. D.B. Matveev, Dr. Eng. Sc. N.I.
Potapov |
|
Method used to determine stress
condition –
vertical exposure
method.
Radiation used
– FeÊα.
Checkpoints
– the most stresses points in the
structural elements of bridges.
Stress Condition Index
– (s1
+ s2)/3.
Results Obtained
Stress check of the load- bearing chains,
ties of the Krymsky Bridge in Moscow revealed the necessity of
repair operations. |
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Application 14.
Physical Metallurgy Expertise of
the Haulage Steel Rope of Lift No. 4
in the Ostankino TV Tower After Fire |
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The expertise waed at the Moscow State University of Steel
and Alloys (Technological University) BPO GOY upon request of
the RF General Public Prosecutor Office |
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Object of check
– two fragments of the haulage role of lift
No. 4:
fragment ¹1 without evident traces of high temperature impact ,
and fragment ¹2 with noticeable traces
of high-temperature impact.
Purpose of check
– to assess rope strength and
nature of destruction
Check was performed
in Moscow condition
with participation
A.V. Lyutsau, Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math.
Sc. A.D. Zvonkov, Dr. Eng. Sc. D.B. Matveev, Dr.
Phys. Math. Sc. J.N.
Parhomenko |
Results Obtained
Portable x-ray diffractometer of «Rikor»
Series established change under the temperature impact in the
condition of rope metal from hard-drawn (after manufacture) into
thermally processed. This, together with other analyses, this
enabled establishing the reason for rope destruction – it
resulted from sort-time creepage under the action of high
temperature and bears plastic nature. |
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Application 15.
Comparison of Residual Stress
Values Obtained by XRD Method Using «RIKOR»
Series Instrument Versus DAVIDENKOV
Method |
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Object of check
–
disk
fragment made of chromium – nickel alloy
Purpose of check
-
methods
matching
Comparison was done in
the premises of Moscow Institute of Steel and Alloys and Salyut
NPO, with participation of A.V. Lyuttsau, Dr. Eng. Sc. A.V.
Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr. Eng. Sc. D.B.
Matveev, Dr. Chem. Sc. N.S. Merkulova. |
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Out of a fragment of a disk made of chromium – nickel alloy, two
samples were cut. The scheme of measurements
to be done with «Rikor» Series Instruments for the samples
prepared for the analysis to be done by the Davidenkov method is
given in figure. Thereafter samples were handed over to N.S.
Merkulova, Salut NPO, for stress analysis following
the Davidenkov method using POVKON TENZOR plant. The resulting
values of stresses along thickness
h of the samples obtained at the POVKON TENZOR plant Ð (Davidenkov
method) are given on fig.2
(sample 1) and fig. 3 (sample 2). Straight lines D and E limit
the interval of residual stress values obtained
using « Rikor » Series instrument. Curves  and Ñ show
distribution of residual stresses in the surface in
case of consecutive removal with etching of the previous surface
layer, which distribution was obtained
following the Davidenkov method.
DAVIDENKOV Method -
Method of layer-by-layer chemical etching of one side of beam
with a predeformed end. The Indentor
mounted on the free end of the beam, based on the beam curvature,
determines the residual stress value
depending on the depth of the etched layer. It is widely used in
aviation industry. It is a destructive
method of checking (can be done only on samples). |
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Results Obtained
Almost
one-hundred percent correspondence between two methods by mean
residual stress values is
noted at a depth of four microns (according to Davidenkov:-225
MPa, according to XRD method:-229
MPA). Since for alloy EP741, the depth of half x-rays
attenuation varies within 4-6 microns, the match of
the results obtained by the two methods, based on the mean
value, can be assessed as ideal. |
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Application 16.
Stress Condition Check of Al2O3
Polycrystals (Polycor) |
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Object of check
– 4 samples of rectangular Al2Î3 polycrystalline (polycor)
plates.
Purpose of check
- was to determine residual stresses in
the samples.
Check was done in the premises
of the Moscow
Institute of Steel and Alloys
withparticipation of A.B. Lyuttsau, Dr. Eng. Sc. A.V. Kotelkin,
Dr. Phys. Math. Sc. A.D. Zvonkov, Dr. Eng. Sc. D.B. Matveev. |
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Method used to assess stress condition
- «Sin2ψ» method.
Radiation used
– CrÊα,
indices HKL: {234}, peak in the area of Θ=680.
Check points - one
check point in center of sample.
Stress Condition Index
– in each checkpoint, the residual
stresses were determined in two mutually
perpendicular directions: σx and σy. Elastic constants used in
the calculation were: the Young module - 380000 MPa, the Poisson
coefficient - 0.3.
Results Obtained
The results are given in the table. |
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Table |
Sample
No. |
σx, MPa |
σy, MPa |
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1 |
-1130 |
-945 |
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2 |
-1540 |
-1045 |
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3 |
-610 |
-300 |
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4 |
+80 |
-960 |
An example of sample diffractomgram |
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Application 17.
Stress Condition Check of Chisels
Made of Steel 40Õ13 and Bronze OCS-555 |
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Object of check -
1. A new puanson made of steel 40Õ132nme of about 300000 cycle.
2.
A chisel having the operation
time of about 300000 cycle within the
temperature range of 20 ... 200 degrees C at 0 to 8
atmospheres pressure.
3. A chisel
made of bronze OCS-555 with operation time of about 300000
cycles within the temperature range of 20…200 degrees C at 0 to
8 atmospheres pressure.
Purpose of check
– was to determine residual stresses of
chisels.
Chisels, Intercross LLC, were checked
at the premisthe Moscow Institute
of Steel and Alloys with participation
es of of A.V. Lyuttsau, Dr. Eng. Sc.
A.V. Kotelkin, Dr. Math. Sc. A.D.
Zvonkov, Dr. Eng. Sc. D.B.
Matveev
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Method used to assess stress condition
-
«Sin2ψ» method.
Radiation used
- FeKα, angle of
diffraction Θ=55.7.
Checkpoints
– in the area of
chisel fins.
Stress Condition Index
– since it was
required to asses the stress condition of chisel in the vicinity
of fins on the whole, the stress condition index was selected as
the mean stress of all checkpoints.
Results Obtained
Mean stress on the fins of new chisel No.1 makes –240 MPa.
Mean stress on the fins of chisel No. 2 makes +72 MPa.
Mean stress on the finds of chisel No.3 withour cracks makes
+190 MPa.
As a result of operation
impact, residual stresses on the fins of the
chisel made of steel 40Õ13 change their polarity
(from compression –240 MPa to tension +72 MPa). For the chisel
made of bronze the tensile stresses are even higher. Residual
tensile stresses impose over effective tensile stresses
leading, in the excess of the elasticity limit, to cracking.
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Publications on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residual stresses
in moldings and parts made of titanium, aluminum, nickel;
and other alloys / Kotelkin A.V., Zvonkov A.D., Lyuttsau A.V.,
Matveev D.B., Kumakhov M.A., Ibraimov N.S. – In Collected
Articles: Die forging: perspectives and development (collected
science reviews ) – GOU VPO «UGTU-UPI», 2005. – pp. 784-790. (in
Russian). |
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Application 18.
Stress Condition Check of a Cast
Iron Forming Roll Fragment |
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Object of check
- a
forming roll fragment made of gray cast iron with a surface
layer of white cast iron.
Purpose of check
-
was to determine residual stresses of the fragment.
Check was done at the premises
of IRO LLC with participation of A.V. Lyuttsau, Dr. Eng. A.V.
Kotelkin, Dr. Phys. Math. Sc. A.D. Zvonkov, Dr. Eng. Sc. D.B.
Matveev, Dr. Phys. Math. Sc. N.S. Ibraimov, A.A. Bolotokov |
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Method used to assess stress condition
-
«Sin2ψ» method.
Radiation used
– CrÊα,
Checkpoints -
the first
checkpoint is on the working surface of the
iron forming, the second
- in the surface layer of white cast iron close to the working
surface, the third one – in the gray cast iron layer far from
the working surface.
Stress Condition Index -
in each
zone, residual stresses in tangential
direction wedetermined.
Results Obtained
On
the working surface of the forming roll (checkpoin
1) the obtained level of residual stresses is close to nil.
In
the tangential direction , in the surface
layer of white cast iron (checkpoint 2), tensile stress was
observed (+90 MPa); further, in the gray cast iron layer
(checkpoint 3) there were compressive stresses (- 60MPa).
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Publications on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining
residual stresses in moldings and parts
made of titanium, aluminum, nickel;and other alloys / Kotelkin
A.V., Zvonkov A.D., Lyuttsau A.V., Matveev D.B., Kumakhov M.A.,
Ibraimov N.S. – In Collected Articles: Die forging:
perspectives and development (collected science reviews) – GOU
VPO «UGTU-UPI», 2005. – pp. 784-790. (in Russian). |
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Application 19.
Stress Condition Check in Steel
ShKh15 Steel Round Billets |
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Object of check
– four billets for fabrication of ball-
bearing rings made of steel ShKh15,
two had scale
on the surface, the other two
were free of surface.
Purpose of Check – was
to determine residual stresses of billets.
Check was done at the premises
of the Moscow Institute for Steel and Alloys with participation
of A.V. Lyuttsau, Dr. Eng. Sc. A.V. Kotelkin, Dr. Phys. Math. Sc.
A.D. Zvonkov, Dr. Eng. Sc. D.B.
Matveev, D.B. Dubrovin |
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Method used to assess stress condition
-
«Sin2ψ» method.
Radiation used
- FeKα
Checkpoints
– in the area of
stress.
Stress Condition Index
– in each zone, residual stresses
were determined in axial (z) and tangential (τ) directions.
Results Obtained
The
inspection results are given in respective bar carts (samples 1,
2, 3 and 4 are marked with red, green, blue, and light blue
color, respectively).
Stresses
in axial
direction do not ultimately render much
influence on ovality of billet
since those are partially eased in the course
of tube cutting into rings. Much greater influence on ovality is
rendered by residual stresses. The data obtained show that in
tangential directions billets 1, 3 and 4 reveal residual
stresses of different polarity, which may lead to their ovality
during their further processing. |
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Publications on the Subject
X-ray diffractometer "RIKOR"
X-ray method of determining residuade of titanium,
aluminum, nickel; and other alloys / Kotelkin A.V., Zvonkov
A.D., Lyuttsau A.V., Matveev D.B., Kumakhov M.A., Ibraimov N.S.
– In Collected Articles: Die forging: perspectives and
development (collected science reviews) – GOU VPO «UGTU-UPI»,
2005. – pp. 784-790. (In Russian). |
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